This invention pertains generally to apparatus for controlling the weight of a food product deposited within a fixed area. In particular, the present invention is a mechanism for depositing a controlled amount of cheese on an upper surface of a pizza crust.
Apparatus for depositing cheese on an upper surface of a pizza crust are generally known. U. S. Pat. No. 4,264,634 to Hochandel et al. discloses one such apparatus for applying grated cheese to pizza shells. The cheese applying apparatus includes a continuous conveyor on which pizza shells are transported from one station to another. Mounted above the continuous conveyor is a grating mechanism and an intermediate transfer conveyor. The intermediate transfer conveyor comprises a continuous belt which is supported in an intermediate relationship between the grating mechanism and the continuous conveyor. The grating mechanism is selectively operable to deposit a layer of grated cheese in a predetermined pattern and layer thickness onto the intermediate transfer conveyor.
The grating mechanism apparatus is of the type which revolves a block of cheese against a fixed grating plate. As the cheese is revolved, it is also pressed forcibly against the grating plate with a predetermined force to maintain the desired uniformity in the amount of material that is removed from the cheese block. The grating plate grates the cheese block into cheese particles which fall onto an upper run of the intermediate transfer conveyor. The intermediate transfer conveyor retains the cheese particles until the transfer conveyor is actuated so as to discharge and deposit an accumulation of cheese particles onto pizza shells as they are moved past the transfer conveyor by the continuous conveyor.
The cheese applying apparatus may include a weight sensor positioned beneath the upper run of the intermediate transfer conveyor. The weight sensor is coupled to the grater mechanism. The weight sensor controls the grater mechanism so that a preset weight of cheese particles are deposited on the intermediate transfer conveyor for ultimate distribution onto the pizza shells. However, the amount by weight of cheese deposited on a pizza shell can vary up to .+-.30% from the preset weight due to inconsistencies in the cheese such as air pockets and density differences.
It is evident that there is a continuing need for improved mechanisms for depositing a controlled amount of cheese on the upper surface of a pizza crust. Specifically, there is a need for a depositing mechanism of efficient design which can consistently achieve a cheese deposit weight variation of no greater than .+-.10% from a predetermined target weight.